Computing machine



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COIPUTING MACHINE Filed June 19, 1948 7 Sheets-Sheet 4 INVE N TOR.

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' JTTORNEU Patented Aug. 14, 1951 COMPUTING MACHINE George A. Just, Scarsdale, N. Y. Application June 19, 1948, Serial No. 33,939

3 Claims.

My present invention relates to computing devices and more particularly to a simplified electrically operated computing device comprising a minimum of operating parts.

My invention also contemplates the arrangement of the computing device so that it may readily be severable or usable in two or more sections whereby the basic computations may be made in one section, container, housing, or arrangement and the results of the computations may be tabulated, recorded, or otherwise made available to the user in another portable section, housing, or key.

Thus, for instance, in automatic merchandising and displayin cabinets, it is desirable not merely to provide arrangements which will deliver goods on insertion of coins or tokens but also to arrange cabinets so that they will deliver goods on actuation by a customer controlled mechanism while at the same time tabulating the value of the goods delivered on a key or other device carried by the customer or assocated in some way with the specific customer. In a food store the various cans or packages of food may be arranged for delivery automatically on energization of proper mechanical or electrical devices.

The purchaser as he enters may be provided with a tabulating key which totals the amounts of the purchases. The customer may then on reaching a desired display insert the key in the appropriate opening for that display connecting electrical circuits between the key carried by the customer and the remainder of the computing machine which may be common to all of the openings, energizing other mechanical or electrical devices to deliver the merchandise and at the same time having the key show either the amount of the purchase or the total of that purchase together with previous purchases.

My present invention is not limited specifically to such automatic delivery devices but is especially concerned with a computing machine which may be housed in a single cabinet as an individual computing machine or which lends itself just as readily to utilization in the foregoing merchandise plan whereby each individual customer or purchaser carries a key which is actually the tabulating part of the computin machine and a single central operating element electrically engaged by the key operates the tabulating elements in the key to add the total of the particular purchase to prior totals.

Essentially, my device contemplates a, drum which is continuously or intermittently rotatable according to the type of operation desired. This drum carries a plurality of contacting elements spaced from each other by insulation and rotating in contact with a number of brushes or other contact members.

Among the contacting elements on the drum are nine bars or electric conductive lines extendin parallel to each other on the circumference of the drum and parallel to the axis of the drum. These bars are successively staggered in length so that a contact which will engage the shortest bar will also engage the eight other bars during a single rotation of the drum, and current will thus flow through that contact during nine spaced intervals for one rotation of the drum.

Thus, any operating element which is intended to indicate or register the number 9 will be connected to a contact which will engage all nine bars during a single rotation.

Similarly, any operating elements which are intended to tabulate or indicate the number 8 will be connected to a contact arranged to intercept only eight of the conducting bars during a single rotation of the drum; and so on down to the point where any operating or indicating element which is intended to indicate the number 1 will be connected to the contact which will engage only one of the bars during the rotation of the drum.

The drum also carries contact elements intended to phase the operations, operate the carry over elements and perform such other operations as are necessary to provide a complete computer.

Thus, for instance, it is important that no change in the setting of the computing device be made during the period that the aforementioned nine parallel bars are passing the tabulating contact.

Therefore, the drum is provided with means which may be electrically operated or mechanically operated, preferably electrical, to lock the mechanism so that no change in its setting may be made during that specific period. This will prevent an incomplete registr or tabulation of a single digit; 1. e., registeringonly 6 when the number 9 is desired.

Where 'my computer is to be used as part of a merchandising scheme, then instead of providing a plurality 01 individual hand pressed buttons or keys for the units tens, hundreds, etc. places on the computing machine, I provide at each opening where the hand carried tabulator is to be inserted a connection to the appropriate contact which engages the nine bars on the drum.

Thus. for instance, if the article to be delivered costs $.19, then in the units place a connection would be made to the plug-in opening for the tabulator mm the contact of the units circuit which engages the nine bars and a connection would be made to the opening into which the tabulator is plugged at that particular delivery point from the contact in the tens place which engages only one of the bars.

For this'purpose, the basic portion of the computer including the drum and its contacts would then be located at a central area, and the nine contacts for the units digits would then be led in a parallel circuit past all of the delivery points.

Similarly, the wires from the nine contacts in the tens place would be led in parallel lines past each delivery point. Each delivery point then would have a single connector for the tens place and, if necessary, a single connector for the hundreds place, one for the thousands place, etc.

In most cases, as for instance in chain grocery stores, connectors would be required only for the units and tens place, except for certain specific counters as for instance the meat counter.

To set up a recording of $.19, the connector of the units place would be clipped to the 9 wire and the connector for the tens place would be clipped to the 1 wire. A price change to, for instance, $.21 would simply require moving the units clip from the 9 wire to the 1 wire and the tens clip from the 1 wire to the 2 wire.

This is made possible by the arrangement of my invention from which a single operating drum may operate one or more tabulating devices. The tabulating devices of my invention are preferably solenoid operated ratchet mechanism individual to each place.

Each actuation of the solenoid at each place operates the ratchet to rotate a tabulating, indicating, or printing wheel one digit.

Thus, when the 9 ratchet is energized for any place, the solenoid for that place will be energized and de-energizcd nine times, operating the ratchet nine times and moving the tabulator, indicator, or printing wheel through nine The carry over from one tabulating, indicating, or printing wheel to the next as, for instance, from the units to the tens is preferably accomplished by a cam on the preceding disc which at the zero point closes a contact in series with the solenoid operator of the succeeding disc.

This contact and the solenoid of the succeeding disc are in turn in series with a contacting element of the operating drum which at the completion of the passage of the nine parallel bars past their respective contacts, energizes the succeeding solenoid once more to add the carry over unit.

Appropriate means are provided to maintain thefirst-mentioned contact closed until the completion of the initial tabulation so that the carry over occurs only after the initial tabulation has occurred.

The primary object of my invention, therefore, is the provision of a novel electrically operated computer comprising a principal operating section and a tabulating or recording section.

Another object of my invention is the provision and arrangement of a. computer of the foregoing type in which one or more tabulating or recording sections may be utilized in conjunction with a single operating mechanism.

Another object of my invention is the arrangement of the operating mechanism of a computer so that the operatingmechanism is cyclically operable and so that during each cycle of operation circuits connected to the tabulating' or recording mechanism may be repeatedly opened and closed a number of times equal to the specific digit which it is desired to tabulate or record at the particular place.

Another object of my invention is the arrangement and provision of a simplified electrically operated computing and recording device utilizing a minimum of electrical and mechanical parts and no gear trains.

The foregoing and many other objects of my invention will become apparent in the following description and drawings in which:

Figure 1 is a schematic view showing the electrical and mechanical operation of my novel device as a single computer; the computing portion of the circuit is detailed in Figure 2.

Figure 2 is a schematic detail of the computing portion of the circuit of Figure 1.

Figure 3 is a schematic view of the operating drum of my invention.

Figure 4 is a view in perspective of the keyboard of my novel device.

Figure 5 is a cross-section through the keyboard of my novel device taken from line 5 5 of Figure 4.

Figure 6 is a schematic view illustrating the application of my invention to a store merchandising scheme.

Figure 7 is a circuit diagram illustrating the application of my invention to multiple keyboards.

Referring first to Figures 1, 2, 3, 4 and 5, the principal operating portion of my device comprises a drum Ill preferably made of insulating material or having an insulating surface driven by motor ll through shaft l2.

The drum I0 is provided with a plurality of parallel conductive bars 9, 8, I, 6, 5, 4, 3, 2, I, the said bars extending on the surface of the drum parallel to each other and parallel to the axisofthedrum.

The bars are of unequal length or at least are staggered at one end so that bar 9 is the shortest and bar I is the longest and the bars in between vary regularly in step by step proportion in length.

In the form shown, bars I to 9, inclusive, are interconnected by the continuous bar l5 of which they may conveniently be made a part. Current is led to the contact bars I to 9 and other contact elements of the drum by conductor 20 leading from line terminal 2| to brush BIB which brush during a portion of the cycle of rotation of drum 50 engages the bar l5. Contact bar I5 extends circumferentially of the drum so that during one portion of the cycle at least bar l5 moves continuously and not intermittently under the contact or brush 22.

The contact members Bl, B2, B3, etc. to B9 arev linearly arranged along a line parallel to the axis of the drum and in contact therewith. The contact buttons lu to Bu, It to St, lh to 971., lm to 9m may be pressed into engagement with respective stationary bars CI to C9 to connect lines 25, 26, 21 and 28 to brushes Bl to B9. These contact buttons may be movable toward and away from the bars, being mounted on buttons or keys hereinafter described as shown in Figures 3, 4 and '5, or they may be continuously in contact with, the drum surface in order to function in connection with the device as it is arranged for use in the modification of Figures 6 and 7.

Contact elements In to 91, inclusive, are each connected to the units conductor 25 in parallel with each other. Thus, as the drum rotates, if the contact 911 has been pressed into engagement with bar C9, it is in a position where it will be energized by all of the bars I to 9, inclusive.

However, if instead contact Bu has been pressed, it engages bar C5, the brush C of which will clear bars 6, I, 8, and 9 not coming in contact therewith and will only engage bars I to 5 as the drum rotates.

Each of the contact members lu to 91!. is, therefore, so located that they will be energized only by the specific number of bars applicable to the digit which the contact is desired to signify in the computing machine.

The movable contacts It, it, etc. to in are each connected in parallel with each other to the tens conductor 26. The operation of these contacts is the same as that previously described in connection with the units contacts, but conductor 26 is connected to operate the tens digit in the tabulator or recorder or printing disc or bar.

The hundreds contacts lh, In. etc. to Sh are connected in parallel with each other to conductor 21 which in turn is connected to operate the hundreds digit section of the tabulator, recorder, or indicator.

These contacts also operate in the same manner as previously described for the units contacts.

The thousands contacts is, 28, etc. to 9s are connected in parallel with each other to conductor 28 which in turn is connected to operate the thousands digit indicator, tabulator, or recorder.

A line of contacts may also be provided for the ten thousands place. another line for the hundred thousands place, and still another line for the millions place and so forth; the number of lines of contacts being limited only by the purpose for which the device is built.

The buttons or keys which operate the contacts may be arranged in rows parallel to each other.

The units tabulator Slu comprises a solenoid 51 u having an armature 52a normally extending upwardly and outwardly from the solenoid and being biased upwardly by the compression spring 5311. The armature 52a passes through the opening 54a in the lever 5521, being provided with collars 56a, 5111 so that any downward or upward movement of the armature 52a will result in a corresponding downward or upward movement of the end of the lever 55a.

Lever 55a is journaled for rotation freely by shaft 60a which carries the ten-tooth ratchet Slu. Lever 55a carries the pawl 62a pivotally mounted thereon at the pin 63a, the pawl being biased into engagement with the ratchet wheel Glu by the coil spring 651;, connected between the pawl and the lever. The ratchet wheel Slu carries keyed thereto the tabulating, recording, or indicating wheel lllu having the digits from 1 to 9 and zero on the periphery thereof.

When now, for instance, contact I u is pushed down into engagement with bar Cl connected to brush Bl engaged only by bar I of drum III, a circuit will be closed to solenoid 5| u from terminal 2|, through conductor 20 and the closed operating switch 30 to conductor 22 and brush Bill to contact bar l5, thence through the bar I, brush Bl, contact bar Cl, contact button lu, units conductor 25 to the solenoid 5hr, from the solenoid 5lu to conductor 12, thence to conductor 13, through the switch 200, conductor 14 and back to the opposite terminal 15. The

8 function of switches It and ill will be hereinafter ducribed.

The solenoid ilu will be energized once when the bar I moves under brush Bl of contact bar Cl. thereby pulling down the armature 52a, pulling down the end of lever 55a, and pulling down the pawl 62a past the ratchet i Iu.

As soon as the bar. I on rotation of the drum leaves the contact bar Cl, the solenoid 5Iu will be de-energized and spring 53a will drive the end of lever 55!; up to drive the pawl 62:: against the ratchet wheel Glu thereby rotating the ratchet one step to the next digit.

Any appropriate friction or holding means may be used on the ratchet ilu to ensure that it will not drift between operations of the pawl 82a and to make sure that it will not move backwards on the upward movement oi the pawl.

If instead of depressing contact button In into engagement with bar CI, contact button Bu is pushed into engagement with bar C9, then as the drum rotates all of the bars I to 9, inclusive. passing successively under the brush B9 will energize and de-energize solenoid 5|u nine times, thereby rotating the ratchet 9 steps, thereby adding the digit 9 to the indicator Mu.

The only limit on the speed of rotation of the drum is thus that imposed by the rapidity with which the solenoid can respond to energization to attract its armature 5211. and the compliance of spring 581: which returns the armature 52a and lever 55a and pawl 62:: to its original position.

The solenoid ma be made very small because the only work it need do with each operation is to move the ratchet wheel Glu and its indicator 16a of a revolution. The stroke of lever 5511 may correspondingly be made small and the spring 531: may be made substantially powerful and with a very short period of vibration.

Thus, when it is desired to tabulate, for instance, the number 5 in the units column, contact button 5a is pressed into engagement with bar C5 connected to brush B5 and in the course of one rotation of the drum the solenoid Slu is energized and de-energized five times to rotate ratchet wheel Hu and indicator Iliu five steps.

Other means hereinafter described, including switches 3| and 200 and their respective holding solenoids, must be provided to ensure that when a particular contact such as contact 511 is pushed into engagement with its bar, the initiation of the energization of the drum will occur just before bar 9 begins to pass under the brushes B and to arrange the unit so that such buttons as have been depressed into engagement with their bars will be raised up out of engagement therewith after all of the operations have been performed by the drum and before the drum completes one full cycle or before the next cycle begins.

Such apparatus for preventing recycling and additional recording of a number or partial recording of a number and for preventing interruption of a cycle will be more specifically described, particularly in connection with the description of the contact buttons.

The tens tabulator, indicator, or recorder Slit operates in exactly the same manner as that described in connection with the units indicator, recorder, or tabulator Stu and the parts thereof have been given the same reference numbers, except that the suilix letter t has been substituted for the suillx letter 1:.

In the case of the tens tabulator Slit, current passes from terminal II and conductor 20, opersting switch 30 to conductor 22, to brush BIO and conducting bar I5, then through any of the bars I to 9 to the particular bar CI to C9 into engagement with which a contact button It to St has been pressed, then through conductor 28 to solenoid 5It, and then through conductor I6, conductor I3, switch 200 and conductor 14 to the opposite terminal I5.

Similarly, the hundreds tabulator, indicator, or recorder 50h operates in the same manner as units 502: and iIIt. Current to energize the solenoid Bill. in the manner as for energization of the solenoid 5Iu passes from terminal 2|, conductor 20, operating switch 30, conductor 22, brush BIO, conducting bar I5 and any or all of the bars I to 9 to the particular contact bar CI to C9 into engagement with which a button IC to 90 has been pressed, then through conductor 21 to solenoid 5Ih, thence through conductor 11 to conductor I3 and through switch 209 and conductor I4 back to the opposite terminal I5.

The thousands tabulator, indicator, or recorder 50m also operates in the same manner as the units member Wu and has been given the same reference numbers with the suflix m in place of the sufllx u.

Current for energizing solenoid 5Im of the unit 50m passes from terminal 2|, conductor 20, the operating switch 30, conductor 22, brush B I 0, contact ring I5, and any of the bars I to 9 to the particular contact bar CI to C9 upon which a contact button Im to 9m has been pressed, then through conductor 28 to the solenoid 5Im, thence through conductor I8, 'to conductor 13 and through switch 200 and conductor I4 back to ter minal I5.

It will thus be seen that in order to place the number I23 on the computer, the operator will depress contact buttons Ih, 2t, and 311. As the drum rotates since contact 31:. engages bar C3,

the brushes of which will engage successively bars 3, 2, and I, solenoid 5Iu will be energized three successive times, turning the ratchet wheel Sin and indicating wheel Iu three digits.

Contact 2t engages bar C2, the brush B2 of which will engage only bars I and 2 and will energize solenoid It twice, turning the ratchet wheel 6It ano the indicator lot ,%'of a revolution or two digits.

Contact Ih engages bar CI, the brush BI of which is engaged only by the contact bar I of the drum to energize solenoid 5Ih only once during the revolution, moving the ratchet wheel Gin and the indicator I0h of a revolution or one digit.

If now after the number I23 has been cleared from the machine and placed on the tabulating disc 'IIIu, Hit, and h, the number 999 is placed on the machine by depressing contact buttons 9h, 9t, and 9a to be added on to the previous indication I23, each of the discs I0u, I0t, and 10h will pass through zero, and it will be necessary to carry over the I0 from each of the discs 10a, "Hit, and 10h to the next placed disc by adding one digit to the next placed disc, in response to the passing of the respective discs through zero.

Thus, the disc IIIu will be carried around by the addition of 999 to 123 through zero to indicate 2. In order to obtain the carry over, the fact that disc I0u reaches zero must result in adding of one unit to the next higher placed disc.

This is accomplished in the case of the transference or carry over from the units disc to the tens disc by the cam 80a located on the units disc or ratchet wheel between the numerals 9 and zero.

As the disc 'IIIu moves from 9 to zero the cam 80u raises the rod 8Iu against the compression of the return spring 82a to close the spring switch 831i. The rod 8Iu is latched upwardly by the engagement of latch 84a in latching detent 85a of the rod BIu, the said latch 841; being biased into engagement by the compression spring 86a.

This prepares a circuit to the solenoid 5It of the tens operator 50t, the switch 83a being energized and closed only at such times as the units indicator IIIu passes from 9 to zero.

If during the passage from 9 to zero as in the case of the addition of 999 to 123 the units indicator continues to retate beyond zero up to the digit 2, the latch 84a nevertheless holds up the rod Bi to maintain the switch 83a in closed position.

Similarly, the tens disc Illt is operated by the rotation of durm it from the digit 2 of number 123 around through zero to indicate 1 by reason of the addition of the tens digit 9 to the tens digit 2.

Likewise, the hundreds disc 19h is operated from i or 123 up to zero by reason of the addition thereto of the hundreds digit 9 of the numher 999.

In each case, the passage of the cam 8011., SM, and 80h past the rod 8Iu, tit, and Mn closes the switches, respectively, 83a, 93L and 8372..

' the carry over.

At the conclusion of the movement of bars I to 9 past the contact, the indication on the tabulating discs 89h, I9 3, and Illu would read 012.

However, the closing of switches I3t and 83h has prepared the necessary circuits to obtain The full rotation of each of the discs I0u, i2t, and Inn has now been obtained by the movement of bars I to 9 of drum III past the contact bars CI to C9 apart from the carry over.

On completion of the movement of bars 9 to I past contacts 9a, 9t, and 9h resulting in an indication of 012, the contact bar IOI passes under the brush BuC. This now establishes, a circuit from terminal 2I, conductor 20, through the switch 30, conductor 22, brush BIO, contact ring I5, bar IOI, brush BuC, conductor I03, solenoid I30u to the now closed switch 83a and then through conductor I 04 to conductor 26 through the solenoid 5It, through conductor I6 and current carrying elements I3, 200, 14, back to terminal I5.

This results in a single additional energization of the tens solenoid 5It to move the indication thereof one digit from an indication of digit 1 to an indication of digit 2.

The carry over from tens to hundreds is operated by the contact bar I06.

When conductor I06 moves under the brush BtC, then if the contactor 83t is closed as it is in the present instance, the circuit is closed to solenoid 5Ih for one impulse of operation from terminal 2|, conductor 21, switch 30, conductor 22, brush BIO, contact ring I5, contact element I06, brush BtC, conductor I09 solenoid I30t, contactor 83t, conductor IIO, to conductor 21 through solenoid 5Ih and through current carrying members 11, I3, 200, I4, back to the opposite terminal I5. This causes the hundreds disc 10h to advance from 0 to 1.

Similarly, as the hundreds disc 10h reached the zero point, the cam actauted rod 8Ih to close the contactor 83h, and thereby prepare a circuit for operation of solenoid Elm of the thousands unit.

when new contact element I15 on the. drum passes beneath brush BhC a circuit is closed to a solenoid Im from terminal 2| through elements 2|, 39, 22, Bil, I5, H5 and BhC to conductor I20, to solenoid Illh, then through contactor 83h, conductor III to conductor 28, through solenoid SIm and current carrying element 19,13, 20', I4, back to the terminal I5.

This causes the thousands indicator s to move from zero to 1, thereby placing the indicators in positions 1, 1, 2, 2, for, respectively, the units 59m, 50h, "t, "a which, of course, is the proper total of 1122 when 999 is added to 123.

The carry overcontact elements I III, I06, and II! are staggered with respect to each other so that a carry over may take place which occurs as a result of a carry over.

Thus, the tens member may end up at the conclusion of a passage of bars 9 to I at the indication 9. A carry over from the units member will result in the movement of a tens member from 9 to 0, thereby requiring a carrying over from the tens members to the hundreds member in response to the carry over from the units to the tens.

By staggering the members III, H18, and H5 so that they engage their respective brushes at spaced successive intervals, a carry over of this type is permitted.

This type of carry over will occur, for instance, when 23 is added to 7'7. The addition of 3 to 7 will result in the original setting up of the carry over as previously described in the unit section, but the addition of the 2 to 7 in the tens place will not result in the setting up of a carry over.

Now, when the carry over elements IIII and BuC operate in conjunction with the closed switch 83a to carry over from the units to the tens place, the 9 in the tens place will be moved to 0, at the same time setting up a carry over from the tens place to the hundreds place. By spacing elements III, I, and II! from each other by a suflicient distance to permit the carry over to be set up especially when it results in response to a prior carry over, full carrying over of all digits can occur.

Thus, when adding 23 to 77 the indication in response to the movement of bars 9 to I on the contacts is 90. When the carry over from units to tens occurs, the indication that then results in response to movement of contact elements IIII under brush But: is 00.

This results in closing switch 831! and preparing the circuit so that when contact element I06 moves under brush BtC the carry over results in the hundreds place producing the proper result of 100.

Thus, the only requirement as to spacing between IOI and I06 and H5 is that sufilcient time be given between them so that a contact 831:, Ht, or 83h may be closed after one of the elementsIIII or I 06 has passed beneath its respective brush and before the next succeeding element passes under its brush.

After the final result has thus been reached on the indicator discs, it is necessary to reset or return such rods 8| as have been raised up to close the contactors 83.

For this purpose, solenoids I30u, Illt, and ISIIh' are provided, the armatures of which constitute the latches Nu, "t, and h, respectively.

Each carry over energization as above described also simultaneously energizes solenoids mu, I3IIt,

I3Ilh or Iflm as the case may be, pulling their 10 armatures 84 to the right and permitting the springs 82 or the spring contact of switches It to drop the member III in response to the unlatching thereof.

Since the brushes BuC, EEG and B710 and their associated contact elements IUI, I, III, are respectively in series with contactors "a, Ni, and 83h which, respectively, are in series with solenoids 5It, 5Ih, 5Is, it will be seen that none of the solenoids will be energized for carrying over purposes unless the contactor 83 of the preceding place is first closed by the passing of the preceding place recording disc III to or through zero.

While here my invention has been demonstrated in connection with four places, it will be obvious that it may be used in connection with as many places ticular computer.

An additional row of contact buttons must be added to engage contact bars CI to C! for each additional place and an additional contactor 88 and its associated elements must be added to the preceding place for each additional place.

Thus, if in the illustration shown in Figure 1 a ten thousands place is added, then an additional contactor 83 would be necessary in the thousands place and the associated elements and cam operator therefor would be required.

If desired, the last place of the series, as for instance the thousands place in the illustration of Figure 1, may be provided with a carrying over contactor l3 and its associated solenoid I30m operated by contact bar II 8 on the drum and brush BmC and connected back to operate solenoid 5Iu for the units place so that the addition may go through zero with the fifth place number being carried in mind.

In this case, the addition of the number 1 to a tabulated total of 9999 would result in the setting of all of the indicators to zero by the carry over operation described.

The ring I5 and bars I to 9 may be made in one piece as may also the bars I ll I06, 5, etc, provided they are zig-zagged as shown in Fig ure 1. If the zig-zag form is not followed, then the connection from bars IIII, I06, etc. should be made beneath the surface of the drum to prevent false operation of the various elements.

Phasing of the various elements is essential. It is necessary that all elements operate at the right point in the cycle and that they be released properly. This can be accomplished by energizing the motor II through an appropriate switch Ila after each number has been set up on the machine and braking or latching the motor shaft at the end of one cycle or by placing a clutch in the output shaft of the motor and latching it closed by a mechanically releasable or solenoid operated latch for one cycle.

I prefer however that the motor II and drum III rotate continuously and to utilize circuit connections which will phase the elements properly ensuring that the buttons I u to 91!, It to M, etc., will be locked up or down as the case may be during the cycle and that all elements will be put back to neutral at the end of the cycle. This is accomplished by switches 30 and 2M.

When switch 30 is closed, all circuits are prepared for operation, when switch 3|! is opened all circuits are opened.

Switch 30 is manually operated to close and is so arranged that it will remain in the condition in which it is left, open or closed as the case may be.

as is required for the par- When a number is set up on the machin switch 30 is manually closed. The drum is as abov pointed out rotating continuously but no closed circuit exists since switch 200 (biased open by spring 200a) is open and the by-pass circuit through solenoid 300 is open at brush Be, the starting brush. The drum, just before the beginning of the cycle rotates to a point where contact bar 30I connected to contact ring I passes momentarily under brush Bs. This energizes solenoid 300 from terminal 2I, elements 20, 30, 22, BIO, I5, 30I, Bs, conductor 302, through solenoid 303, conductor 304, solenoid 300, and the conductors 305 and 16 to the opposite terminal 15.

Solenoid 300 attracts the armature of switch 200 to close the switch against theopening spring 200a. Solenoid 306 is then energized to hold switch 200 closed, the circuit for solenoid 306 extending from terminal 2I and elements 20, 30 and 22 to conductors 301,303 and 303 through solenoid 3I0, conductor 3 to solenoid 306, then through conductor 3I2, switch 200 and conductor 14 to the opposite terminal 15.

Solenoid .303 will operate the locking plate I hereinafter described. Solenoid 3I0 may operate any auxiliary arrangement that may be required at the end of the cycle.

Since switch 200 is in circuit with conductorJS, the computing units 60 operate only after switch 200 is closed. Contact bar 30I on the drum determines thetime of, closing of switch 200 and hence the beginning of the cycle.

v Contact'bar 30I therefore is first to engage its brush Bs. Thereafter, the other contact bars engage their brushes in the order 9, 3, 1, 6, 5, 4, 3,

2, I, IOI, I06, H6 and H0. Lastly the contact bar 3 I5 engages brush BR, the releas or end-ofcycle brush. I This closes a circuit to solenoid 320 which pulls switch 30 open, de-energizing all circuits. Solenoid 320 is momentarily energized from terminal 2I over elements 20,.30, 22, IBIO, I5, 3I5, BR conductor 32I, solenoid 320, conductor 322 and elem nts 306, 306, 3I0, 3", 306, 3I2, 200, 14 to the opposite terminal 15.

Solenoid 330, in parallel with solenoid 320, now pulls the locking plate I13 hereinafter described I60 at the portion thereof which passes througl slot I6l in the latching plate I62. An individua. slot may be provided for each shaft I50 of each button and its associated latch I60, or a single longitudinal slot or rail may be provided for each row of buttons.

When a button is pressed down to bring its associated contact against the contact bar CI, C2,

- etc., the spring latch I60 snaps under the opening i6I in plate I62 and holds the button and its contact against the surface of the bar. The particular' button which has been depressed will hold its contact against the surface of the contact bar until the latching plat I62 is moved to the left with respect to release the latch I60 and permit 7 the compression spring I56 to raise the button to backto non-locking position and solenoid 222 in parallel with solenoid 320 simultaneously pulls the latch plate to the left to disengage the buttons which have been depressed and to permit the I springs to return these butons to the raised posi tion. 7 Y

a Contact bar 3I5 is thus the end-of-cycle bar and its engagement with brush BR ends the cycle.

If the number is to be repeated, it is only necessary to place a normally closed switch in the circuit of brush BR to operate it to open position by a "repeat button and the number will be repeated for the number of cycles of drum I0 that the repeat button is pressed, making multiplication possible.

The contact buttons Iu to M, It to St, etc., each comprises, asseen in Figures 4 and 5, a vertical shaft I at the lower end of which is secured the contacting element m, h, t, or u, as the case may be. Nine buttons or keys are provided and, accordingly, nine contacts 71., t, and u, are provided for each plate to engage the bars CI, C2, etc.

The shaft I of each button passes through aligned openings I5I, I52 in the mounting plates I53, I54. A collar I55 on each button shaft I50 comprises a spring I56 between itself and the lower mounting plate I 54, thereby biasing each button upwardly. v

Each button is also provided with a spring latch snap it up again.

Consequently, whatever number is to be tabulated is placed on the machine by pressing the appropriate buttons for that number. Thus, for the number I23 the In button in the hundreds place, the 2t button in the tens place and the 3a button in the units place are depressed, each of these buttons being held down by the engagement of its latch I60 beneath the latching plate I62.

The drum rotates and the solenoids are energized to operate the indicators, tabulators, or recorders in accordance with the buttons which have been depressed as previously described and the number I23 is placed on or added to the machine.

Where the drum I0 is being rotated continuously, it is important that phasing be properly accomplished so that none of the buttons can be pressed or pushed down while the bars I to 9 are passing under the contact brushes and so that none of the buttons can be lifted up accidentally during that'particular phase of the cycle.

In order to accomplish this result, each of the shafts I50 is provided with a pair of notches I10 and "I, the corresponding notches I10 and "I being aligned with respect .to similar notches on all the other buttons.

Above the latching plate I62 is mounted the stop plate I15 having a plurality of longitudinal bars I16. The bars I16 extend along the rows of button shafts I50, one bar for each row of buttons.

In the up position of the buttons, the notches I1I of each button are opposite the bars I16. In the down position of the buttons the notch I10 of each button is opposite the bar I16.

When now a button is depressed so that the latch I60 is caught on the plate I62, the notch I1I moves down from the bar I16 and the notch ,I10 moves opposite the bar I 16.

Just before the first bar 9 on the drum begins to move beneath the contacts, solenoid 303 is energized to attract its armature 2I I. Armature 2 is connected to the left side of plate I15.

Energization of solenoid 303 pulls the plate I15 to the left, pulling the bars I16 to the left. The bars I16 enter the notches III of the buttons which have not been depressed, and the notches I10 of the buttons which have been depressed and lock the buttons in raised or lowered position, preventing any change in their position while the contact elements of the drum are moving under the contacts which engage the drum. On completion of that portion of the cycle of the drum during which contacts of various kinds are made, the solenoid 303 is de-energized by opening of switch 30 while at the same time sole noid 330 is momentarily energized to pull the 1 plate I15 to the right and locking bars I and permitting the buttons to be operated. A spring may be substituted for solenoid 330 to bias plate I to the right at all times.

The latching plate I62 is so mounted that it is biased to the right to latching position by springs 220.

Solenoid 222 is provided with an armature 223 connected to the left side of the plate I62. Solenoid 222 i in parallel with solenoid 320.

Therefore, at the end of the cycle, solenoid 222 is energized to pull the latching plate I62 to the left and release all of the depressed buttons, permitting the spring I56 to snap them up once more.

The energization of solenoid 222 should occur simultaneously with the de-energization of solenoid 303 and energization of solenoid 330 so that the locking bars I16 move to the right at the same time as the latching plate I62 moves to the left, thereby permitting the tabulating keys to rise.

The solenoid 303 and hence the locking bars remain de-energized and out of locking position during the period between the operating portion of the cycle, while the latchin plate I62 is pulled momentarily to the operating cycle.

The utilization of the locking bars I16 prevents false operation of the buttons or any operation intermediate or during the operating portion of the cycle so that false tabulation or improper setting up or clearance of numbers cannot occur during the operating portion of the cycle. Also the switch 200 ensures that the operation will begin at the proper point in the cycle and contact 3 I 5 and brush BR ensures that the operation will end at the proper point in each cycle.

In the construction shown herein, errors can be corrected before pressing switch button 30. The correction of such errors may be obtained by a push button connection for solenoid 222 on the latching plate, connecting it directly across terminals 2| and 15, to pull the latching plate to the left and lift the buttons before any recording operation is obtained, or a mechanical means may be provided to push latch plate I62 to the left to release all buttons.

The indicators, tabulators, or recording elements I0u, I0t, 10h, and 10m may have any de-- sired form and may, if desired, contain or operate printing elements in conjunction with any printing apparatus well known in the art in order to record successive totals as they are reached by the machine, adapting my invention for use in cash registers and other devices where permanent recording is desired.

For this purpose, additional contacts on the drum may operate a pressure bar to bring a sheet of paper with a ribbon against its surface or other suitable printing devices may be used energized by an appropriate contact on the machine.

In Figure 6 I have shown my invention adapted to a store merchandising plan in which the customer is provided with a key 400 containing esthereby removing the sentially the accumulator apparatus shown in. Figure 2 and the operation of which will now be understood from the prior description of Figure 2 taken in connection with Figure 1.

Hence, all of the elements in the key 400 have been given the same reference numbers as the identical elements in Figures 1 and 2.

Instead, however, of having the accumulator apparatus directly connected to the impulse generating apparatus of Figure 3 or the left-hand left just at the end of the- 14 end of Figure 1, the leads 26, 26, and 21 which, respectively, energizes the solenoids 6Iu, 6I t, and. 6 Ih are connected to the prongs 25a, 26a, and 21a of the jack 40I of the key 400.

Likewise, the carry-over connections I03, I09, and I20 instead of being directly connected to the impulse generator are connected to the prongs I03a, I09a, and I20a of the jack 40I of the key 400.

Also, the return circuit I3 for the accumulator apparatus instead of being connected to terminal I5 as shown in Figures 1 and 2 is connected to the prong 13a of jack 40L The various prongs 25a, 26a, 21a, ISIa, iIISa, I20a, and 13a of jack 40I may now be plugged into the contacts 25,26, 21, I03, I09, I20, and II in the socket 402. A plurality of sockets 402 are pro vided, each individual to the particular merchandising element.

When the customer goes into a store, he or she is given the key 400 containing the accumulator elements. When she sees a particular display from which she desires to make a purchase, she may pick up the piece of merchandise and at the same time plug the key 400 into the socket 402. The price of that purchase will be added to the total on her accumulator in the manner hereinafter described.

Since, however, the design of Figure 6 is intended primarily for chain stores where much time has previously been lost in the totaling of merchandise when it was brought to the checking desk and where a substantial amount of merchandise has been lost by pilferage, it is intended that my device including the key 400 be utilized in connection with vending devices which on the closing of a circuit or on mechanical actuation will deliver the item.

For this purpose, the key may include a circuit connection for a mechanical element which unlocks the display cabinet and energizes a delivery device which will deliver the item.

At the same time, the circuit connection made by the key will add the price of the unit to the total on the key.

The vending elements themselves do not constitute a part of my present invention, but the means by which the accumulator apparatus from the key 400 adds on the specific total constitutes the specific adaptation of my invention to such a merchandising scheme.

The connecting elements 25, 26, and 21 for units, tens, and hundreds in the socket 402 are provided with individual contact clips 425, 426, and 421 electrically connected to the circuit connecting elements 25, 26, 21 in the socket.

The contact bars CI through C9 of the apparatus of Figure 1 connected to the impulse generator which includes the drum I0 of Figure 3 are extended behind all of the displays as a continuous set of nine parallel conductors with taps at convenient locations running the length of the display and vending machines.

Where the price of an individual item to be merchandised is $1.25, the hundreds clip 421 will be clipped to bar Cl; the tens clip 426 will be clipped to bar C2; and the units clip 425 will be clipped to bar C5.

Should the price then be changed to $1.15, it will be necessary only for the store manager to move the tens clip 426 from bar C2 to bar CI.

Thus, prices may be set up and readily changed simply by moving the clips around. The clips 425, 426, and 421 thus constitute the equivalent of the buttons u, h, t, and m of Figures 4 and 5, being treated as if these buttons were continuously depressed and only one button for each place were provided.

Similarly, the carry-over connections I03, I09, and I which determine the carrying-over of one place to the next when the lower place goes through zero are carried to the leads I03, I09, and I20 which pass behind all of the displays. The carry-overs will be energized from contacts IOI, I06, and I I5 of the impulse generator located at the central point. I

Consequently, the key 400 by simply being plugged into the socket 402 will be connected up so that the individual key and the central impulse generator will correspond to the unit illus: trated in Figure 1.

It is necessary, however, that control means be provided individual to each key to ensure that when it is plugged in while the switch 200 of Figure 1 is closed and the impulse generator is somewhere in the middle of a cycle that the remainder of the cycle will not register on the key 400 and that the key will register only for a complete cycle.

For this reason, the central impulse generator will not have the contact 200 and the magnets 300 and 300. Instead, the contact 200A, the magnet 305a, and the magnet 300a will be provided at each socket location 402.

Switch 200a will be located in circuit between the lead I3 and terminal I5 as previously described in connection with Figure 1. However, the circuit will be broken at the gap 430, and leads 43 I and 432 extend from this gap to contacts 433 and 434.

The plug 40I is provided with the bridging contact 435 which when the plug 40I is inserted in socket 402 will bridge contacts 433 and 434 placing the magnet 30641 in a condition to be energized when contact I on the drum passes brush BS.

If this were not done or if the circuit to magnet 300a were not broken at the gap 430, then the magnet 306 may be energized to close the switch 200a every time the drum rotates and the possibility will then exist that a key may be inserted in the middle of a cycle to produce registry of only part of the cycle.

Since the circuit is broken at the gap 430, magnet 3050 cannot be energized by the engagement of contact 30I with brush BS until after the key is inserted and the circuit to the magnet 30011 is closed by the bridging contact 435 in engagement with contacts 433 and 434.

Consequently, the magnet 306a will be energized to close the switch 200a when contact 30l on the drum passes the brush BS at the beginning of a cycle following the insertion of plug I of key 400 in the socket 402.

The magnet 3050 will then pull the switch 200a closed whereupon the magnet 3000. will be energized to hold the switch 200a closed in exactly the manner described in connection with Figure 1, except that the solenoid 303 in series with ma net 300 of Figure 1 may be omitted.

The impulse generator now going through its cycle will operate the accumulator apparatus in the key 400 to add the particular cost of the item to the total on the key 400. 3

At the end of the cycle, the solenoid 320 connected on one side to lead 32 I which in turn is connected to brush BR at the impulse generator and on the other side to the terminal I5 will be energized to extend its armature 450, pushing against the abutment I of the plug 40I and thereby pushing the plug 40I out.

The energization of magnet 320 which corresponds to magnet 320 of the unit described in connection with Figurel thus prevents the next recycling of the impulse generator from repeating the addition and adding a successive total.

At the same time, the magnet 320a or a magnet similarly connected may be utilized to energize the delivery apparatus. Since it is not desirable to have the magnet 320a energized unless a key is actually inserted in the socket, the circuit to magnet 320a is broken at 455. Leads 450 and 451 on opposite sides of the gap 455 are connected to contacts 458 and 459.

An additional bridging contact 460 is carried by the switch 200, being connected thereto by the insulated extension 40I. When switch 200a is pulled .down to close, it pulls down the bridgin contact 400 to bridge contacts 450 and 459 and, therefore, prepare a circuit for operation of the magnet 320a after switch 20011 is closed. Magnet 320a thus cannot be energized until switch 2000 is closed.

Switch 200a cannot be closed by energization of magnets 306a and 3000 until bridging contact 435 is inserted in the circuit therefor.

Thus, magnet 320a cannot be energized unless the key 400 has registered a full cycle; and the key cannot begin to register any part of the cycle until contact 30! on the drum of the centrally located impulse generator passes brush BS after the key is inserted.

As may now be understood, the impulse generator of the left-hand end of Figure 1 and of Figure 3 is located at some central source in the store.

The bars CI through C9 extend continuously behind all the displays and are accessible for engagement by clips 425, 420, and 421. The leads 3, 32I, I03, I09, I20, and I5 may be housed in a cable from which individual connections are made to the sockets at each display.

Socket 402 at each display has prongs 25, 26,

and 21 which are connectable to the bars CI to C9 and prongs I03, I09, I20 connected to the similarly numbered leads, as well as prong I3 which is connected through switch 200a to lead I5.

The prongs are contacted by the similarly num-j bered prongs on the plug 401. The contacts 433 and 434 are bridged by the bridging contact 435 on the plug 40I. A switch 200a with its additional bridging contact 400 is located at each socket, and magnets 320a, 306a, and 300a are located at each socket.

It will be obvious that this system of using a centrally located impulse generator and individual keys may be applied not only to store merchandising but to various other types of operations including stock rooms, in factories or stores, warehouses, for inventory control and other related uses where individual sets of figures are to.

be totaled in accordance with the withdrawal of units from a stock.

The unit may be combined with automatic delivery mechanism or in the case of warehouses and stock rooms, the automatic delivery mechanism, which forms no partof the present invention but which may be energized by magnet 320a or an electrical circuit in parallel therewith, may be dispensed with.

In the case of chain stores, the utilization of the system of Figure 1 as modified in connection with the showing of Figure 6 makes it unnecessary to use a skilled checking clerk to price and total the merchandise since the customer need 17 merely present the key showing the correct total with the merchandise.

The checking desk, therefore, in a chain store will simply be a wrapping or packaging desk, and a single cashier may be used in place of the multiple cashiers and checking clerks heretofore used Since my invention as disclosed in connection with Figure 1 lends itself as shown in connection with Figure 6 to separation of its various elements, my novel device may be used in a form wherein a single impulse generator of the type of Figure 10 may control a multiplicity of accumulators.

This is shown schematically in Figure 7 where each adding machine 500 will have an individual keyboard of the type of Figure 4 and an individual accumulator of the type of Figure 2. The keyboard has the bars Clo to C90. connected to the prongs lb, 22;, through 9b of the plug 50L The energizing lead 22a is connected to the prong 22b. The start lead 302a is connected to the prong 30212. The units lead I03a is connectedto the prong I03b. The tens lead I03a is connected to the prong I09b. The hundreds lead 1200 is connected to the prong l20b. The thousands lead 5030. is connected to the prong 503b, and the release lead 32Ia is connected to the prong 32Ib. l

The individual adding machine thus connected to the plug 50I will have parts which correspond to all of the elements of Figures 1, 2, 4, and 5, except for the elements shown in Figure 3 and, therefore, the elements shown to the left of line 505 and above line 506 of Figure 1.

The leads from the terminals of Figure 3 and from the various brushes shown therein and in the schematic view of Figure 1 are connected to a cable l0 to which a plurality of sockets are connected. Each socket 5| I is provided with connectors individually connected to each of the leads of cable 5m and arranged to match the connecting prongs of the plug 50I.

Thus, a central impulse generator may be used energizing the leads in cable 5") and individual adding machines without the impulse generator of Figure 3 or left-hand end of Figure 1 may be provided with plugs 50l to be plugged in at suitable locations wherever sockets 5| I are provided.

By this means, therefore, the individual adding machines need only consist of the accumulator elements of Figure 2 plus the keyboard of Figure 4 and the associated magnets 306, 300, 303, 320, 222, and 330 and the associated switches 200 and 3 As far as size is concerned, therefore, each individual adding machine may have lateral dimensions which need be only the size of the keyboard itself plus a suflicient extension to permit the numbers on wheels in of Figure 2 to be visible and a depth which is determined only by the height of the keyboard including the distance from contact bars CI to the top of buttons 3m, 971., St, and 91: plus a depth sufiicient to house magnets 306, 300, 303, 320, 222 and 330 and the switches 200 and 30. The switch 30 should, of course, be located in a position accessible from the top of the keyboard.

By this means, therefore, a plurality of small size adding machines may be operated from a single impulse generator reducing the cost of installation of a large number of adding machines and making each of the adding machines a small compact unit.

While I have shown my invention in connection with a specific type of accumulator and a specific 18 type of impulse generator, it will be obvious that many variations and modifications may be made.

Thus, instead of generating impulses which are transmitted to the solenoids of individual counters, the individual counters may be connected to the rotating drum or on the shaft thereof, and the electrical impulses generated by the rotating drum as above-described may be utilized to energize electro-mechanical elements to cause the counters to rotate with the drum or at a rate proportional to the rotation thereof for that portion of the revolution of the drum determined by the impulse or specific energization created by the revolution of the drum.

Thus, individual counters may be connected by magnetic clutches to the shaft of the drum and currents controlled by the drum may be utilized to energize and de-energize the magnetic clutches to control the angular rotation of each counter in response to the current controlled by the drum 'and in response to specific selecting or control elements contactors of Figures similar to the buttons or 4 and 5.

In another and obvious modification of my invention, a single accumulator of the type of Figure 2 may be utilized in connection with a large number of adding machines being connected in parallel with the device of Figure 2 as connected to Figure 1 or being so arranged that the individual adding machines have no accumulator at all but simply the keyboard.

In this way, individual adding machines would consist of nothing but the keyboard of Figure 4. A central generator of the type of Figure 3 would be used. This generator-would be connected to the sixteen leads shown across the top of Figure 7.

Each keyboard plug would then have only prongs corresponding to the prongs lb to 9b of Figure 7 and another set of prongs for connection to the leads 25, 26, 21,. and 23 of Figure 1. Leads 25, 26, 21, and 23 would then go to the central accumulator and the remaining leads 302, I03, I03, I20, IBM, and 22 of Figure 1 would also go to the central accumulator.

Thus, in machines of the para-mutual type where it is desired only to know a single total, each operator would be provided with just a keyboard connected by a. suitable plug to a cable containing leads for the contact bars CI through C3 and leads to the elements 302, I03, I09, I20, 32I, and 22.

The accumulator would then show the total of operations of all adding machines.

This will require, as above pointed out, a central impulse generator, a central accumulator, and a plurality of keyboards, each of which need contain only the elements shown in Figures 4 and 5.

For added security in operation, each keyboard may also contain the switch 30 and the switch 200 and associated magnets to control the operation.

. In department stores where individual totals as well as composite totals are required, a master accumulator may be connected to all of the addin machines in parallel with the accumulators individual to adding machines.

This type of operation is also desirable in warehouses and in many other accounting systems where individual and composite totals are required.

The only difliculty that may arise is that when impulses are received simultaneously from two or more adding machines, a pair of such imerably an electrical retain the impulses until the master accumulator pulses occurring together may result in only a single operation of the master accumulator;

To obviate this,-it may be necessary to provide in the connection between each individual adding machine andthe accumulator a. relay which will disconnect the adding machine from the accumulator if the impulses from another adding machlneare being registered and will instead energize either an auxiliary accumulator or prefmemory device which will and likewisein the constructions of Figures 6' and 7 I have shown the various elements interconnected electrically b wire.

My invention also contemplates that in large multiple installations the circuit connections need not necessarily be by direct wire but may be obtained by suitable radio transmitters and receivers working on appropriate frequencies of limited broadcasting range or direct telephone or telegraph wire, where desired.

Also, by interconnecting the units by radio,

telephone, or telegraph, it will be possible for chain stores or a type of business having many branches to obtain instantaneous master totals at some specific central point. 1

Also, where desired, appropriate re-setting devices may be used to return the indication on the machine to zero after the completion of a tabulating operation. Such devices 'may be either mechanically. or electrically operated and may follow any of the well known principles already used in standard adding machines.

However, it will be obvious that the carry-over cams 80 on each of the discs ID may well furnish a mechanical element which can be interengaged by any re-setting device. One such resetting device may be a plurality of fingers concentric to each other, each individual toa specific disc lll, operated simultaneously by a knob accessible from the outside of the machine. A single rotation of the knob will cause the individual fingers to engage the extensions or cams N of the discs Ill and return them to the desired position. Y

The fingers are preferably mounted on the shaft which is operated by the externally accessible knob, the shaft being spring biased to a position where the fingers are out of the plane of the cams 80. To re-set the discs 10, the knob should then be pressed in to bring the fingers into the plane of the cams 80 and then rotated. Automatic mechanical means maybe provided to pull the shaft over to the proper position at the initiation of the re-setting operation and to push the shaft back to non-engaging position at the end.

Various electrical re-setting devices may be used, as for instance-each of the'discs '10 may have a contact engaging the plurality .of contacts at different positions of the discs paralleling the bars CIto C9. Thus when a 'disc is at position 4, the contact engaged thereby within the accumulator will be in parallel with bar 06. In this position, closing a switch to energize the accumulator through the said complementary contacts will automatically add to the accumulator a number which will bring the total on the accumulator to zero. 1

As above pointed out, my novel device and sy tem is obviously applicable to multiplication'in 1 the manner presently used by the. art. Various thereto to fa-.

automatic means may be added cilitate such operations; 7 1

For subtraction operations it will only be necessary to duplicate each of the ratchets BI and to duplicate the pawls operated by the solenoids.

The addition would be accomplished by the ratchet andpawl as shown. The ratchet and pawl for subtraction would then work in an opposite direction.

To shift from addition to subtraction, it would then only be necessary to renderone set of pawls inoperative and permit the other set of pawls to work. This can be accomplished by appropriate mechanical means which will either shift the solenoid 5| to the left orright as a group, or their armatures 52 left or right as a group, or simply the pawl carriers at the top of the armatures left or right as a group.

Since these many variations and modifications of my invention should now be obvious to those skilled in the art, I prefer to be bound not by the specific disclosures herein contained but only by I the appended claims.

I claim: 1. An electrical computing device comprising accumulating apparatus responsive to electric current pulses to accumulate and register the algebraic totals of successive pulses; electric current pulse generating aparatus generating a suc-' cessive series of successive pulses, each series including nine pulses and a plurality of control pulses; said pulse generating apparatus comprising a continuously rotating member having a contact member secured to it; said contact member comprising a rake-shaped section and a stepsnaped section, said sections being formed in combination and integral with each other; said rake-shaped section comprising at least nine prongs of different graduated lengths; said step-- shaped section comprising at least one step for each of said elements registering the digits; a-

first'and a second plurality of circuit connecting members for the pulse generating apparatus, each connecting member of said first plurality of connectingmembers being responsive to and energized'by a pre-selected group of the nine pulses of the series pulses each connecting member of said first plurality of connecting members being spaced to intermittently engage a difierent num- 1 her of prongs of said rake-shaped section of said contact member during'each revolution of said continuously-rotating member; each of said second plurality of connecting members being responsive to and energized by a single pre-selected pulse; each of said second plurality of contact members continually engaging a difierent step of said step-shaped section of said contact member during a different portion of a revolution of said continuously rotating member; and means interconnecting the electric current pulse generating apparatus and the accumulating apparatus, said last-mentioned means comprising a plurality of individually selectable and operable contactors each movable to interconnect electrically the pulse generating apparatus and the accumulating aparatus, individual contactors being mow.

able into and out of engagement with individual circuit connecting members of the pulse generating apparatus, said individual contactors being prevented from moving into and out of engagement with said individual circuit connecting members of said pulse generating apparatus when said pulse generating apparatus and electro-mechanical accumulating apparatus are energized; said pulse generating apparatus being energized when one of the second plurality of connecting members engages one of the steps of said contact member, said individual contacts being moved out of engagement with said individual circuit connecting members when said one of the second plurality of connecting members disengages said one of the steps of said contact member.

2. An electrical computing device as in claim 1 wherein the electric current pulse generating apparatus and the accumulating apparatus are separate units; and wherein the means interconnecting the electric current pulse generating apparatus and the accumulating apparatus comprises a manually separable and unitable connector.

3. An electrical computing device as in claim 2 wherein .the electric current pulse generating apparatus is provided with a plurality of interconnecting means; and wherein a plurality of able with any of the interconnecting means of the electric current pulse generating apparatus.

GEORGE A, JUST. REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 515,110 Callender Feb. 20, 1894 15 518,885 Hollerith Apr. 24, 1894 1,302,616 Williams May 6, 1919 1,933,353 Tauschek Oct. 31, 1933 2,283,999 Kozma et a1. May 26, 1942 2,293,127 Fishack et a1. Aug. 18, 1942 20 2,353,046 Lake et al. July 4, 1944 2,398,771 Compton Apr, 23, 1946 2,402,989 Dickinson July 2, 1946 2,432,324 May Dec. 9, 1947 FOREIGN PATENTS 25 Number Country Date 112,677 Australia Dec. 9, 1949 244,013 Germany June 3, 1909 

